We are facing an issue with an iPhone 16 Pro device where VoLTE is not supported/activated. Due to this, the user is unable to make normal (offline) video calls to Android users.
iPhone 16 Pro, iOS 26
E, 2G, 3G, 4G, LTE, VoLTE, and 5G all are Carrier Specific features. Contact your Carrier (Cellular Service Provider), the agency that issued the SIM / eSIM to you. About the LTE options on your iPhone - Apple Support (IN)
See the Pic below and the explanations thereof
The pic below is self-explanatory
iPhone 16 Pro VoLTE not supported for Android video calls
